// MIT License

// Copyright (c) 2019 Erin Catto

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include "test.h"

class ConvexHull : public Test
{
public:
  enum
  {
    e_count = b2_maxPolygonVertices
  };

  ConvexHull()
  {
    Generate();
    m_auto = false;
  }

  void Generate()
  {
    b2Vec2 lowerBound(-8.0f, -8.0f);
    b2Vec2 upperBound(8.0f, 8.0f);

    for (int32 i = 0; i < e_count; ++i)
    {
      float x = 10.0f * RandomFloat();
      float y = 10.0f * RandomFloat();

      // Clamp onto a square to help create collinearities.
      // This will stress the convex hull algorithm.
      b2Vec2 v(x, y);
      v = b2Clamp(v, lowerBound, upperBound);
      m_points[i] = v;
    }

    m_count = e_count;
  }

  void Keyboard(int key) override
  {
    switch (key)
    {
    case GLFW_KEY_A:
      m_auto = !m_auto;
      break;

    case GLFW_KEY_G:
      Generate();
      break;
    }
  }

  void Step(Settings& settings) override
  {
    Test::Step(settings);

    b2PolygonShape shape;
    shape.Set(m_points, m_count);

    g_debugDraw.DrawString(5, m_textLine, "Press g to generate a new random convex hull");
    m_textLine += m_textIncrement;

    g_debugDraw.DrawPolygon(shape.m_vertices, shape.m_count, b2Color(0.9f, 0.9f, 0.9f));

    for (int32 i = 0; i < m_count; ++i)
    {
      g_debugDraw.DrawPoint(m_points[i], 3.0f, b2Color(0.3f, 0.9f, 0.3f));
      g_debugDraw.DrawString(m_points[i] + b2Vec2(0.05f, 0.05f), "%d", i);
    }

    if (shape.Validate() == false)
    {
      m_textLine += 0;
    }

    if (m_auto)
    {
      Generate();
    }
  }

  static Test* Create()
  {
    return new ConvexHull;
  }

  b2Vec2 m_points[b2_maxPolygonVertices];
  int32 m_count;
  bool m_auto;
};

static int testIndex = RegisterTest("Geometry", "Convex Hull", ConvexHull::Create);
